The August 21st, 2017 total solar eclipse will be a once-in-a-lifetime event for many people. A little preparation now can ensure that you and your family enjoy the event and keep your eyes healthy, The American Academy of Ophthalmology and the American Astronomical Society are working together to make sure everyone knows how to watch the coming eclipse safely.
“Looking directly at the sun, even while it’s partially eclipsed, can potentially cause permanent damage vision or blind you,” says John Hanlon, M.D., Ophthalmologist and Chief Medical Officer at Little Company of Mary Hospital (LCMH). “The below tips are important to keep in mind during the total solar eclipse.”
- Always inspect your solar filter before use; if scratched or damaged, discard it. Read and follow any instructions printed on or packaged with the filter.
- Always supervise children using solar filters.
- Stand still and cover your eyes with your eclipse glasses or solar viewer before looking up at the bright sun. After looking at the sun, turn away and remove your filter — do not remove it while looking at the sun.
- Do not look at the uneclipsed or partially eclipsed sun through an unfiltered camera, telescope, binoculars, or other optical device.
- Similarly, do not look at the sun through a camera, a telescope, binoculars, or any other optical device while using your eclipse glasses or hand-held solar viewer — the concentrated solar rays will damage the filter and enter your eye(s), causing serious injury.
- Seek expert advice from an astronomer before using a solar filter with a camera, a telescope, binoculars, or any other optical device. Note that solar filters must be attached to the front of any telescope, binoculars, camera lens, or other optics.
- If you are within the path of totality (https://go.nasa.gov/2pC0lhe (link is external)), remove your solar filter only when the moon completely covers the sun’s bright face and it suddenly gets quite dark. Experience totality, then, as soon as the bright sun begins to reappear, replace your solar viewer to look at the remaining partial phases.
- Outside the path of totality, you must always use a safe solar filter to view the sun directly.
- If you normally wear eyeglasses, keep them on. Put your eclipse glasses on over them, or hold your handheld viewer in front of them.
The safest way to look directly at the uneclipsed or partially eclipsed sun is through special-purpose solar filters, such as “eclipse glasses” or hand-held solar viewers. Homemade filters or ordinary sunglasses, even very dark ones, are not safe for looking at the sun; they transmit thousands of times too much sunlight. Refer to the American Astronomical Society (AAS) Reputable Vendors of Solar Filters & Viewers (link is external) page for a list of manufacturers and authorized dealers of eclipse glasses and handheld solar viewers verified to be compliant with the ISO 12312-2 international safety standard for such products.